Hemodynamic measurements with an abdominal 4D flow MRI sequence with spiral sampling and compressed sensing in patients with chronic liver disease

J Magn Reson Imaging. 2019 Apr;49(4):994-1005. doi: 10.1002/jmri.26305. Epub 2018 Oct 14.

Abstract

Background: The test-retest/interobserver repeatability and diagnostic value of 4D flow MRI in liver disease is underreported.

Purpose: To determine the reproducibility/repeatability of flow quantification in abdominal vessels using a spiral 4D flow MRI sequence; to assess the value of 4D flow parameters in diagnosing cirrhosis and degree of portal hypertension.

Study type: Prospective.

Subjects: Fifty-two patients with chronic liver disease.

Field strength/sequence: 1.5T/spiral 4D flow acquired in one breath-hold.

Assessment: Thirteen abdominal vessels were identified and segmented by two independent observers to measure maximum and time-averaged through-plane velocity, net flow, and vessel cross-section area. Interobserver agreement and test-retest repeatability were evaluated in 15 and 4 cases, respectively. Prediction of the presence and severity of cirrhosis and portal hypertension was assessed using 4D flow parameters.

Statistical tests: Cohen's kappa coefficient, coefficient of variation (CV), Bland-Altman, Mann-Whitney tests, logistic regression.

Results: For all vessels combined, measurements showed acceptable agreement between observers, with Cohen's kappa = 0.70 (P < 0.001), CV < 21%, Bland-Altman bias <5%, but high limits of agreement ([-75%,75%]). Test-retest repeatability was excellent in large vessels (CV = 1-15%, bias = 1-25%, Bland-Altman limits of agreement [BALA] = [4%,150%]), and poor in small vessels (CV = 7-130%, bias = 10-200%, BALA = [8%,190%]). Average velocity in the right hepatic vein and average area of the splenic vein were higher in cirrhosis (P = 0.027/0.0039). Flow in the middle hepatic vein strongly correlated with Child-Pugh score (ρ = 0.84, P = 0.0238), while flow in the splenic vein (ρ = 0.43, P = 0.032), time-average (ρ = 0.46, P = 0.02) and peak velocity in the superior mesenteric vein (ρ = 0.45, P = 0.032), and peak velocity in the infrarenal IVC (ρ = 0.39, P = 0.032) positively correlated with an imaging-based portal hypertension score. Average area of the splenic vein predicted cirrhosis (P = 0.019; area under the curve AUC [95% confidence interval, CI] = 0.87 [0.71,1.00]) and clinically significant portal hypertension (P = 0.042; AUC [95% CI] = 0.78 [0.57-0.99]).

Data conclusion: Spiral 4D flow allows comprehensive assessment of abdominal vessels in one breath-hold, with substantial interobserver reproducibility, but variable test-retest repeatability. 4D flow may potentially reflect vascular changes due to cirrhosis and portal hypertension.

Level of evidence: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:994-1005.

Keywords: 4D flow; cirrhosis; liver fibrosis; phase contrast MRI; portal hypertension; spiral.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abdomen / diagnostic imaging
  • Adult
  • Aged
  • End Stage Liver Disease / diagnostic imaging*
  • Female
  • Hemodynamics*
  • Humans
  • Hypertension, Portal / diagnostic imaging*
  • Image Processing, Computer-Assisted / methods
  • Imaging, Three-Dimensional*
  • Liver / blood supply
  • Liver Cirrhosis / diagnostic imaging*
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Observer Variation
  • Prospective Studies
  • Regression Analysis
  • Reproducibility of Results